Question about venturi tube on Macchi 202 serie 3

Post topics relating to fighters, bombers, ground attack aircraft, transports, powerplants, ordnance, armament, materials construction, design, secret weapons, flak, radar, ground equipment (e.g., autotreno 3000)
Post Reply
Fred Kennamer
Pilota
Posts: 2
Joined: Sun Oct 04, 2009 2:55 am
Location: Los Angeles, CA

Question about venturi tube on Macchi 202 serie 3

Post by Fred Kennamer » Mon Apr 26, 2010 10:56 pm

I'm finally within sight of finishing the Pacific Coast 1/32 kit, and can't find one bit of detail on-line or in the old Profile Publication, Ali D'Africa, Aero Detail C200/202/205, Squadron Macchi 202, Squadron Macchi 205 Walk-around, Ali D'Italia or others.

The venturi tube was on the belly just forward of the radiator, and was centered, just forward of the seam for the center access panel. There are photos in these books to show that the elongated horn-like affair was mounted on a pylon, with an open tube coming out of the center pylon forward, and another tube coming out of the pylon and curving into the wing. The question is this: did that smaller tube go into a hole pierced into the panel, or get snuck in via the panel's aft seam.

The only photos I've found looking up at the underside of the wing is one in the Aero Detail book with the tube (sans smaller tubes) placed in the wrong area during restoration, and noted as such.

Thanks in advance for the help.

Rick
Generale di Brigata Aerea
Generale di Brigata Aerea
Posts: 243
Joined: Mon Nov 13, 2006 10:31 am
Location: Florence, Italy

Tubo di Venturi

Post by Rick » Tue Apr 27, 2010 9:49 am

Sorry, due to my imperfect kwnoledge of your language, I was not able to clearly understand your question.
My advice is to consult the original document "Catalogo Nomenclatore per velivolo da Caccia Aer. Macchi C202 (1^ tranche)" you can find in the Italian site
www.modellismopiu.it

entering the G.I.S. Regia Aeronautica and going to the page where the instrument panel appear, of course in this document you can find a lot of information useful for a correct modelistic reproduction.

Both front and rear surface of Venturi tube whee open to allow the air transition.

Of course to enter the site and to enter the GIS documentation you have to perform a registration

Hoping this can help
Riccardo
Riccardo Trotta

Stefano
Generale di Brigata Aerea
Generale di Brigata Aerea
Posts: 170
Joined: Sun Nov 12, 2006 2:40 pm
Location: Padua, Italy

Post by Stefano » Tue Apr 27, 2010 10:20 am

Other than what suggested by Rick, I think this page from the maintenance manual could be useful.

Image

Stefano

Rick
Generale di Brigata Aerea
Generale di Brigata Aerea
Posts: 243
Joined: Mon Nov 13, 2006 10:31 am
Location: Florence, Italy

Request for Stefano

Post by Rick » Tue Apr 27, 2010 12:18 pm

Per favore Stefano, puoi dare un'occhiata al mio post sul sito del 150° relativo al Breda 65 K14
Grazie
Riccardo
Riccardo Trotta

Fred Kennamer
Pilota
Posts: 2
Joined: Sun Oct 04, 2009 2:55 am
Location: Los Angeles, CA

thanks guys; it's still not clear, but that's great info

Post by Fred Kennamer » Wed Apr 28, 2010 8:58 pm

What a wealth of information in those original manuals. I wish I knew about them before scratchbuilding the interior of the wheel wells; I got part of the coolant lines in the wrong place. Ah well...

Still, there are many great details for things I'm still working on, and that site is a great resource.

My question is this: the venturi tube looks like a horizontal horn on a pylon facing aft, with a short tube coming out of the pylon on the front, and another bit of tube coming out of the pylon on the back and curving up into the fuselage. From the many photos from profile and to the side, this tube must go into either a hole in the big central access panel, or be tucked into a notch in the middle of the back end of this panel.

Page 57 of Ali D'Italia #22 has a photo of one from slightly below with the panel removed and a dangling tube; is this the tube? Does this mean it goes into the seam and not into a hole cut into the back end of the panel? I can't find any photos that show the detail.

Thanks for all the help! I should actually be done fairly soon.

User avatar
MDriskill
Comandante di Gruppo
Comandante di Gruppo
Posts: 56
Joined: Thu Oct 03, 2019 4:35 am
Location: Tennessee

Re: Question about venturi tube on Macchi 202 serie 3

Post by MDriskill » Mon Jun 27, 2022 12:13 pm

The C.202's underside venturi location may have varied some. On many aircraft it was not dead center as in the AeroDetail drawings, but offset and further forward as shown in the wartime manual drawing posted above, and in Ali d'Italia's drawings. And on late C.202's and the C.205, it moved to a completely new spot on the starboard fuselage side.

The only photos I know of that have the separate tubes that you describe, are in the Squadron Walk Around book, showing such a side-mounted unit on a C.205. On belly-mounted venturis, the small vacuum tube up to the instruments seems to be enclosed within its mounting pylon...though again, there might be variations.

Here's another amazing page of manual information by the way: http://www.cmpr.it/manuali.htm

Image

Image

Post Reply